Why Hitting Broken Electronics Can Make Them Work: The Science Behind “Percussive Maintenance”

As much as we rely on technology these days, there is a common bond between almost all electronic components of or daily lives: At some point they are going to screw up. So what do most people instictually do when a piece of electronic equipment messes up?

We smack it.

Almost miraculously, more times than not, this is the fix. Curious about this phenomenon, I decided to do some research. As it turns out, this conundrum not only has an official name, “Percussive Maintenance”, but it actually has a scientific basis.

Why it Works

“Percussive Maintenance”, also known as “Impact Calibration”, “Mechanical Agitation”, or even the “the Fonzarelli Fix”. No matter what you call kinetic forms of re-adjustment, there is actually a scientific reason that it works. According to Mack Blakely, executive director of the National Electronics Service Dealers Association: “In the old days, devices had a lot of mechanical stuff in ’em, and you could jar something back in place.” Blakely, who has been an electrical engineer for almost 50 years, explains that when it comes to electronics, “A solder connection might reconnect, but it probably wouldn’t be long before it would be acting up again. A few well-placed taps may identify a weak connection on a printed circuit board. The word ‘tap’ is important, it’s not ‘hit;’ it’s ‘tap.’”

The scientific/mechanical definition of ‘hit’ versus ‘tap’ is up to the operator’s discretion.

NASA Uses It

An example of “percussive maintenance” is action occurred on NASA’s Apollo 12 space mission. As the official transcripts show, there was a problem with one of the many cameras that were streaming video and audio back to Earth. The following conversation took place between astronaut Alan Bean and support crew member Edward Gibson:

Gibson: There’s no change down here, Al. (Pause) That’s coming in there, now, Al. Okay, what change did you make?
Bean: I hit it on the top with my hammer. I figured we didn’t have a thing to lose.
Gibson: Skillful fix, Al.
Bean: I hit it on the top with this hammer I’ve got. (Responding to Gibson) Yeah, that’s skilled craftsmanship.

If percussive maintenance is good enough for NASA, I have to conclude that is good enough for me.